Because of the importance of the blue crab for the Chesapeake Bay, both as a predatory species and as an object of prey, many scientists are studying the blue crab.

At SERC, senior scientist Anson (Tuck) Hines and staff in the Estuarine Fish and Invertebrates Lab have been studying the blue crab for many years. The researchers at SERC, for example, are asking questions about the movement of blue crabs. Where do they go and how much do they move around during the day? Where do crabs molt if there are not underwater grasses in most of the Bay? How males interact with other males, and when and where do crabs feed?

Where do they go?

Studying blue crabs, however, may sound easier than it is. How can you find out where the crabs go in the Bay when you can't even see more than one foot into the water column?

The researchers at SERC have been very creative and come up with a few methods to follow and study the blue crab in its natural habitat. Dr. Hines, together with his colleague, Tom Wolcott from North Carolina State University, has designed electronic telemetry transmitters that are light enough to be able to be attached to the back of the crab.

Male blue crab with telemetry device that SERC researchers use to track the crab's location.

This "tag" transmits a signal through the water at a certain frequency (similar to a radio signal). The scientists then use a hydrophone and a receiver to pick up the signal. This way, they know where the crab is.

Anson "Tuck" Hines tracks crabs on the Rhode River using a receiver and hydrophone

Over the years, the tags have gotten more advanced. The researchers now use a variety of tags to follow the crabs movement and feeding habits.